Laser used for quicker and cheaper monitoring of molten steel

Ordinarily, steel plants have to regularly halt production while a disposable probe gets lowered into the molten steel, measuring its temperature and collecting samples for chemical analysis. That may not be the case for much longer, though, thanks to a new laser-based inspection system.

The current probe-based system costs steel producers money, both in terms of lost production time and the cost of the probes themselves. Developed at Britain's Swansea University by a team led by Dr. Szymon Kubal, the laser system has neither of those drawbacks.

It involves projecting a laser beam into a steel furnace and onto the surface of the molten steel within, via a channel called a tuyère in the furnace wall. This is done while production is still in progress, with gas being continuously injected into the tuyère in order to keep the channel clear. Utilizing a partially-proprietary process, the system is able to measure the temperature and chemical composition of the steel.

"The method is spectrometry-based and records data from the light emitted by the steel either passively (for temperature) or after excitation with the laser source (for composition)," team member Dr. Cameron Pleydell-Pearce explains to us.

The technology has been tested at the Tata Steel Port Talbot steelworks, and is now being commercialized by Swansea spinoff company Kubal-Wraith Ltd. It can reportedly also be used to monitor the production of metals such as aluminium, copper and nickel.